Universal gasket for laparoscopic cannula

ABSTRACT

A laparoscopic cannula gasket apparatus for sealing around an instrument within a cannula includes a first member having an internal passageway, an elastic sleeve member within the passageway, a structure for securing a first segment of the sleeve member to the passageway, a second member rotatably connected to the first member, a structure for securing a second segment of the sleeve member to the second member, the first and second segments of the sleeve member being spaced apart so that a portion of the sleeve member extends between the first and second segments, such that rotating the second member relative to the first member stretches the portion of the sleeve member between the first and second segments to progressively form an annular diaphragm extending radially inward from the passageway to make sealing contact with the instrument. The first member is preferably a cylinder attached to an end of a cannula by a flattened out end portion so that the passageway is essentially coaxial and aligned with the longitudinal axis of the cannula. The elastic sleeve member is preferably a latex material. The structure for securing the first segment of the sleeve member preferably includes a recess in the passageway and an annular member fit within the recess, between which the first segment is compressed. The structure for securing the second segment preferably includes a port in the second member having a port edge and an annular member fit against the port edge, between which the second segment is compressed.

This application is a continuation-in-part of application Ser. No.08/027,718, filed on Mar. 8, 1993 now abandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to the field of cannulas forlaparoscopic examination and surgery, and more specifically to a gasketassembly for sealing around an instrument to prevent loss of air underpressure inside the abdominal cavity, the assembly including a firstmember with a central internal passageway for receiving instruments, thepassageway containing a universal gasket including a cap having acentral port and a lip with an inward projecting flange rotatably fitinto a groove around the circumference of the first member, the caphaving a central hole aligned with the passageway and a first ring witha circumferential exterior groove fit resiliently over the edge of a thecentral port, a second ring being resiliently fitted into a recessaround the passageway entrance, and a latex sleeve fit at one end snuglybetween the first ring and the cap and at the other end snugly betweenthe second ring and the first member, so that rotating the cap and firstring relative to the second ring stretches the middle portion of thesleeve extending between the rings, the tension in the sleeve in turncausing the middle portion to close radially inward and to make sealingcontact with an object extending through the passageway, regardless ofthe diameter of the object, and rotating the cap in the oppositedirection releases the object and opens the passageway.

2. Description of the Prior Art

There have long been cannulas for providing laparoscopic access forvarious procedures. Some of these cannulas have required the use ofvarious reducers to close the space between the cannula walls and eachinstrument placed within the cannula, to prevent loss of gas from theabdominal cavity. A problem with these reducers is that a differentreducer must be used for each instrument having a diameter differentfrom that of the previous instrument. Changing reducers can lead to lossof critical time and carries the risk that the proper reducer may bemissing at a crucial moment.

Berry, et al., U.S. Pat. No. 5,158,553, issued on Oct. 27, 1992,discloses a rotatably actuated constricting catheter valve. Berryincludes a hub which is joined to the catheter, and a rotatable capwhich is joined to the hub. An elastomeric sleeve is positioned in anopening through the interior of the valve body. One end of theelastomeric sleeve is joined to the rotatable cap and the other end isjoined to the hub, so that turning the cap collapses the sleeve aroundan instrument within the opening. The Berry sleeve must extend throughtwo annular members, necessarily making the collapsing sleeve portionrelatively long. A problem with Berry is that when the Berry members arerotated to close the valve, the elongated sleeve collapses to formessentially a tubular contact surface, gripping the instrument along awide band. This wide sleeve contact creates a high friction grip whichprevents ready axial or rotational movement of the instrument within theopening or passageway. While such movement may not be necessary to thecatheter use emphasized in Berry, it is necessary in laparoscopicsurgery.

Knepshield, et al., U.S. Pat. No. 4,177,814, issued on Dec. 11, 1979,reveals a self-sealing cannula. Knepshield includes a slottedelastomeric valve positioned in a valve seat with the slot disposed overthe passage. The elastomeric valve is compressed to seal the slot, thussealing the cannula passage around any instrument within the passage.Knepshield includes a thick block or mass of elastic material which hasa closed central slit and is compressed in a contracting compartment tocreate a sealing bulge around an instrument. The problems of Berry etal. are again presented.

It is thus an object of the present invention to provide a universalgasket assembly which can seal around an infinite variety of instrumentdiameters and thus replaces reducers.

It is another object of the present invention to provide such a gasketassembly which can be readily and securely incorporated into existinglaparoscopic cannulas.

It is another object of the present invention to provide such a gasketassembly which uses a short sleeve portion to generate a thin diaphragmgasket, making essentially line contact with an instrument in theassembly, so that instruments can be moved within the assembly withminimal friction resistance

It is still another object of the present invention to provide such agasket assembly which can simplify and expedite the performance of manylaparoscopic procedures.

It is still another object of the present invention to provide a methodto make an air-tight connection between the gasket and the cannula.

It is finally an object of the present invention to provide such agasket assembly which can be inexpensively manufactured from well known,conventional surgical materials.

SUMMARY OF THE INVENTION

The present invention accomplishes the above-stated objectives, as wellas others, as may be determined by a fair reading and interpretation ofthe entire specification.

A laparoscopic cannula gasket apparatus is provided for sealing aroundan instrument within a cannula, including a first member having aninternal passageway, an elastic sleeve member within the passageway, theelastic sleeve member being formed of a sleeve member material having anaverage thickness, structure for securing a first segment of the sleevemember to the passageway, a second member rotatably connected to thefirst member, structure means for securing a second segment of thesleeve member to the second member, the first and second segments of thesleeve member being spaced apart so that a gasket-forming portion of thesleeve member extends between the first and second segments, so thatrotating the second member relative to the first member stretches theportion of the sleeve member between the first and second segments toprogressively form an annular diaphragm of stretched sleeve membermaterial extending radially inwardly from the passageway toprogressively close around and make sealing contact with the instrument,where the structure for securing the second segment of the sleeve memberincludes a port in the second member having a port edge and a secondannular brace having an axial depth and having two member edges and fitwithin the port and against the port edge, the sleeve member secondsegment being anchored between the port edge and the second annularbrace, and extending over a member edge of the second annular braceopposite the first member, and then doubling back inside and through thesecond annular brace, where the passageway in the first member has aninner wall, and the structure for securing the first segment of thesleeve member includes a first annular brace having an axial depth andwhich is positioned within and across the passageway to follow thepassageway inner wall, and the first annular brace is spaced apart fromthe second annular brace a distance greater than the average thicknessof the sleeve member material for permitting the sleeve member to passbetween the first and second annular braces without binding between thefirst and second annular braces when one the annular brace is rotatedrelative to the other annular brace, and the sleeve member extendsbetween the first annular brace and the passageway inner wall so thatthe first segment is anchored between the first annular brace and thepassageway inner wall, so that the length of the gasket-forming portionof the sleeve member exposed within the passageway is limited tosubstantially the axial depth of the second annular brace, to form athin diaphragm gasket to permit minimally restricted movement oflaparoscopic instruments within the internal passageway while theinstruments are engaged by the gasket.

The first member is preferably a cylinder attached to an end of acannula by a flattened out segment so that the passageway is essentiallycoaxial and aligned with the longitudinal axis of the cannula. Theelastic sleeve member is preferably formed of a latex material. Thestructure for securing the first segment of the sleeve member preferablyincludes a recess in the passageway and a first annular member fitwithin the recess, between which the first segment is compressed. Thisconnection is made air-tight by means of epoxy or similar cement that isaccumulated in a small space around the first segment of the sleeve. Thestructure for securing the second segment of the sleeve memberpreferably includes a port in the second member having a port edge andan annular member fit against the port edge, between which the secondsegment is compressed. The apparatus preferably additionally includes aflap valve within the passageway, the flap valve being mounted on a pinmember and biased into a closed position with a biasing mechanism. Anend of the pin member preferably protrudes through the exterior of thefirst member, and additionally includes a lever attached to theprotruding end of the pin member. The second member is preferably a caphaving a lip and an inwardly directed flange on the lip slidably fittinginto a circumferential groove around the exterior of the first member.The cap optionally includes calibration markings for indicating how farthe cap is rotated relative to the first member. The apparatus mayadditionally include a nozzle protruding from the first member tointroduce gas into the passageway, from an end of a hose. The nozzleadditionally includes a stopcock for controlling the flow of gas throughthe nozzle.

A laparoscopic cannula gasket apparatus is also provided for sealingaround an instrument within a cannula, including a first member having afirst opening with a first opening inner surface, an elastic sleevemember within the first opening, the elastic sleeve member being formedof a sleeve member material having an average thickness, structure forsecuring a first segment of the sleeve member to the first opening innersurface, a second member having a second opening with a second openinginner surface and being rotatably connected to the first member,structure for securing a second segment of the sleeve member to thesecond member, the first and second segments of the sleeve member beingspaced apart so that a gasket-forming portion of the sleeve memberextends between the first and second segments, so that rotating thesecond member relative to the first member stretches the portion of thesleeve member between the first and second segments to progressivelyform an annular diaphragm of stretched sleeve member material extendingradially inwardly from the opening inner surfaces to progressively closearound and make sealing contact with the instrument, where the structurefor securing the first segment of the sleeve member includes a firstannular brace having an axial depth and having two member edges andpositioned within and across the first opening to follow the firstopening inner surface, where the structure for securing the secondsegment of the sleeve member includes the second member second openingand a second annular brace having an axial depth and fit within thesecond opening and against the second opening inner surface, and thesleeve member extends between the second annular brace and the firstopening inner surface so that thesecond segment is anchored between thesecond annular brace and the second opening inner surface, so that thelength of the gasket-forming portion of the sleeve member exposed withinthe first and second members is limited to substantially the axial depthof the first annular brace, to form a thin diaphragm gasket to permitminimally restricted movement of laparoscopic instruments within thefirst and second members while the instruments are engaged by thegasket, where the first annular brace is spaced apart from the secondannular brace a distance greater than the average thickness of thesleeve material for permitting the sleeve member to pass between thefirst and second annular braces without binding between the first andsecond annular braces when one the annular brace is rotated relative tothe other annular brace, the sleeve member second segment being anchoredbetween the first opening inner surface and the first annular brace, andextending over a member edge of the first annular brace opposite thesecond member, and then doubling back inside and through the firstannular brace.

BRIEF DESCRIPTION OF THE DRAWINGS

Various other objects, advantages, and features of the invention willbecome apparent to those skilled in the art from the followingdiscussion taken in conjunction with the following drawings, in which:

FIG. 1 is a side view of the inventive gasket assembly shown mounted ona cannula with a trocar inserted through the gasket, the flap valve andthe cannula. FIG. 1a is a close-up projection view of the nozzleassembly seen in FIG. 1.

FIG. 2 is a cross-sectional side view of the preferred embodiment of theinventive gasket assembly, having the optional flap valve feature.

FIG. 3 is a top view of the cap of the gasket assembly showing thecalibration markings and having the universal gasket open.

FIG. 4 is a view as in FIG. 3, except that the universal gasket is shownclosed.

FIG. 5 is a cross-sectional side view of the assembly with the gasketclosed as in FIG. 4, showing the short axial depth of the sleeve, andthe sharp converging contact edge of the sleeve, which would makeessentially line contact with an instrument.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As required, detailed embodiments of the present invention are disclosedherein; however, it is to be understood that the disclosed embodimentsare merely exemplary of the invention which may be embodied in variousforms. Therefore, specific structural and functional details disclosedherein are not to be interpreted as limiting, but merely as a basis forthe claims and as a representative basis for teaching one skilled in theart to variously employ the present invention in virtually anyappropriately detailed structure.

Reference is now made to the drawings, wherein like characteristics andfeatures of the present invention shown in the various FIGURES aredesignated by the same reference numerals.

First Preferred Embodiment

Referring to FIGS. 1-3, a universal gasket assembly 10 is disclosed foruse with a laparoscopic cannula 12 for inserting through a patient'sabdominal wall. Gasket assembly 10 includes a first member 13 with aninternal passageway 16 for receiving trocar or laparoscopic instruments20. First member 13 comprises a cylindrical portion to engage the flangeof a cap 34 and a flattened-out portion 15 to accommodate a flap valve80 and a nozzle 90.

Gasket assembly 10 includes an inventive universal gasket 30 for sealingpassageway 16 around an instrument 20 of any diameter to prevent escapeof gas from the abdominal cavity. Universal gasket 30 includes a cap 34having a lip 32 with an inward projecting flange 36 rotatably fit into agroove 38 around the cylindrical portion 14 of member 13. At thecylindrical portion 14 of member 13 there is a lip 39 that preventsspillage of fresh cement between lip 32 of cap 34 and first member 13.Cap 34 has a central port 40 with an edge 42, and has calibrationmarkings 44 around the cap 34 perimeter. A first ring 46 has acircumferential external groove 52 which fits resiliently over edge 42.A second ring 62 has a circumferential external groove 53 and isresiliently fit into a recess 66 extending around the entrance 68 ofpassageway 16. An elastic sleeve 70 is fit at one end snugly betweenfirst ring 46 and edge 42 of port 40, then turns around the outer edgeof ring 46 to become positioned inside ring 46. Sleeve 70 is fit at itsother end between second ring 62 and recess 66 of cylindrical portion ofmember 13. It should be noted that there is a small space at groove 53between the sleeve and recess 66 intended to accumulate an epoxy orsimilar cement in order to make the connection between sleeve 70 andfirst member 13 airtight.

Passageway 16 contains a flap valve 80 mounted on a pin 82 and biasedtoward a closed position with a spring, for preventing the escape of gasfrom the abdomen. Flap valve 80 is deflected into an open position whena trocar or an instrument 20 is inserted through passageway 16 andcannula 12. Flap valve 80 also may be operated with an external lever 84attached to pin 82.

A nozzle assembly 90 is optionally provided, including an opening 92 inthe flat portion of member 14 to insufflate gases through passageway 16.A nozzle member 94 protrudes from opening 92, and a stopcock valve 96 isprovided in nozzle 94. See FIGS. 1 and 1a.

Sleeve 70 is preferably made of a latex material. The remainder ofgasket assembly 10 is preferably made of a suitable plastic.

Method

In practicing the invention, the following method may be used. Rotatingcap 34 and first ring 46 relative to second ring 62 in a given directionstretches the middle portion 100 of sleeve 70 between rings 46 and 62.The tension in the latex in turn causes middle portion 100 toprogressively close radially inward and make sealing contact with aninstrument 20 extending through passageway 16. Middle portion 100stretches to form a diaphragm similar to the shutter of a camera. SeeFIGS. 4 and 5. Sealing contact with an instrument 20 is createdregardless of the diameter of instrument 20. This contact is verynarrow, and is effectively line contact with instrument 20, creating anair-tight seal and yet permitting the instrument 20 to be freely movedand manipulated within passageway 16. Rotating cap 34 in the oppositedirection releases instrument 20 and opens passageway 16.

While the invention has been described, disclosed, illustrated and shownin various terms or certain embodiments or modifications which it hasassumed in practice, the scope of the invention is not intended to be,nor should it be deemed to be, limited thereby and such othermodifications or embodiments as may be suggested by the teachings hereinare particularly reserved especially as they fall within the breadth andscope of the claims here appended.

I claim as my invention:
 1. A laparoscopic cannula gasket apparatus forsealing around an instrument within a cannula, comprising:a first memberhaving an internal passageway, an elastic sleeve member within saidpassageway, said elastic sleeve member being formed of a sleeve membermaterial having an average thickness, means for securing a first segmentof said sleeve member to said passageway, a second member rotatablyconnected to said first member, means for securing a second segment ofsaid sleeve member to said second member, said first and second segmentsof said sleeve member being spaced apart so that a gasket-formingportion of said sleeve member extends between said first and secondsegments, such that rotating said second member relative to said firstmember stretches said portion of said sleeve member between said firstand second segments to progressively form an annular diaphragm ofstretched sleeve member material extending radially inwardly from saidpassageway to progressively close around and make sealing contact withsaid instrument, wherein said means for securing said second segment ofsaid sleeve member comprises a port in said second member having a portedge and a second annular brace having an axial depth and having twomember edges and fit within said port and against said port edge, saidsleeve member second segment being anchored between said port edge andsaid second annular brace, and extending over a member edge of saidsecond annular brace opposite said first member, and then doubling backinside and through said second annular brace, wherein said passageway insaid first member has an inner wall, and said means for securing saidfirst segment of said sleeve member comprises a first annular bracehaving an axial depth and which is positioned within and across saidpassageway to follow said passageway inner wall, and said first annularbrace is spaced apart from said second annular brace a distance greaterthan said average thickness of said sleeve member material forpermitting said sleeve member to pass between said first and secondannular braces without binding between said first and second annularbraces when one said annular brace is rotated relative to the other saidannular brace, and said sleeve member extends between said first annularbrace and said passageway inner wall such that said first segment isanchored between said first annular brace and said passageway innerwall, such that the length of said gasket-forming portion of said sleevemember exposed within said passageway is limited to substantially theaxial depth of said second annular brace, to form a thin diaphragmgasket to permit minimally restricted movement of laparoscopicinstruments within said internal passageway while said instruments areengaged by said gasket.
 2. An apparatus according to claim 1, whereinsaid first member is essentially a cylinder attached to an end of acannula such that said passageway is essentially coaxial andsubstantially aligned with the longitudinal axis of said cannula.
 3. Anapparatus according to claim 1, wherein said elastic sleeve member isformed of latex material.
 4. An apparatus according to claim 1, whereinsaid means for securing said first segment of said sleeve membercomprises a recess in said passageway and said first annular brace fitswithin said recess, between which said first segment is compressed. 5.An apparatus according to claim 4, further including a pin memberwherein an end of said pin member protrudes through the exterior of saidfirst member, additionally comprising a lever attached to said end ofsaid pin member.
 6. An apparatus according to claim 1, wherein saidsecond member is a cap having a lip and an inwardly directed flange onsaid lip slidably fitting into a circumferential groove around theexterior of said first member.
 7. An apparatus according to claim 6,wherein said cap includes calibration markings for indicating how farsaid cap is rotated relative to said first member.
 8. An apparatusaccording to claim 1, additionally comprising a nozzle protruding fromsaid first member in gas communication with said passageway, forreceiving an end of a hose.
 9. An apparatus according to claim 8,wherein said nozzle additionally comprises a nozzle valve forcontrolling the flow of gas through said nozzle.